Expansion-pulley.



N6. 664,966. j Patnted 1an. .1', |901.

' n.6. Evi-:nerr I EXPANSIUN P ULLEY.

f (Application led July 6, 1900.) (No Model.) 2 Sheets-Sheet l.

ma Nonms PErsns ca, PHoraLlmo.. WASHINGTON. n. c,

No. 664,996. j Y Patented lan. l, l90l.

' A.S. EVERETT.

EXPANSION PULLEY.

(ppnention med July e, 1900.)

(No Model.)

2 Shoots-Sheet 2. I

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UNITED STATES PATENT OFFICE.

ARTHUR S. EvERE'rT, oF LAWRENCE, MASSACHUSETTS.

vEXPANSION-PULLIY.

SPECIFICATION forming part of Letters Patent No. 664,996, dated January1, 1901.

Application iled July 6, 1900.

To all whom t may concern.

Be it known that I, ARTER S. EVERETT, a citizen of the United States,residing at Lawrence, in the county of Essex and State of Massachusetts,have inventedA certain new and useful Improvements in Expansion-Pulleys;and I do hereby declare the following to be a full, clear, and exactdescription of the in- Vention, such as will enable others skilled inthe art to which it appertains to make and use the same.

My invention relates to expansible pulleys and belongs to that class ofbelt-driven wheels wherein independent segments are simultaneously movedeither toward or from the center, thereby decreasing or increasing thediameter of the revoluble body directly acted upon by the belt. As thesegments are usually precisely alike, their outer surfaces, whichtogether constitute the face of the belt-wheel, are parts of the samecylindrical surface. It is evident that at all but one particular pointof their outward and inward adjustments they do not form exactlycylindrical wheel-faces. This is immaterial, however, as the unavoidablevariance from a true cylinder is found in practice to diminish the clingof the belt very little, if at all.

The objects of my invention are to simplify and improve the constructionand to produce au expansible pulley in which the several .segments areclamped between one fixed and one movable side disk or flange, by meansof which the segments are rigidly held in place after being adjusted.

Each constituent element of my invention is described in detail and itsindividual office,

together with the mode of operation of the whole, fully explainedin'this specification.V

Of the accompanying drawings, throughout which like letters designatelike parts, Figure l represents a side view with a portion of one diskcut away to discloseV one of the adjustable segments shown in verticalsection. Fig. 2 is a vertical cross-section. In this view but one of thesegments is shown. As these elements are precisely the same in everyrespect, structurally and in operation, it is thought that illustratingand describing one segment will answer for all of them. Fig. 3 is aniuside view of the relatively-fixed disk or side of the wheel. Fig. 4 isan inside View of the Serial No. 22,711. (No model.)

clamping-disk. Fig. 5 is an edge view of the4 fixed disk,showing the hubporti0n,thebroken lines denoting the hollow of the hub and theshaft-bore. Fig. 6 is an edge view of the clamping-disk, and Fig. 7 isan outside View of the pressure-plate. The Scale of drawing is reducedin Figs. 3, 4, 5, 6, and 7.

Considering Figs. 2 and 4 of the drawings, letter A marks therelatively-xed dis k, which has a hub a, provided with a centralshaftbore a' and a larger cylindrical open-ended cavity a2, to be againmentioned.

In Figs. 3 and 5 will be noted the inwardlyprojecting guides a3 01,3upon the inner surface of disk A. These guides are formed in pairsparallel with each other and with a radius of the disk drawn midwaybetween them. There are as many pairs of guides as there arereciprocative segments. In the form'illustrated there are eight pairs ofguides, accommodating eight segments, although it is believed to bewithin the purview of my invention to employ any desired number ofsegments.

Considering Figs. 2, 4, and 6, letter B marks the loose clamping-disk.This disk as ordinarily cast has a central circular opening b. In Fig. 6it will be observed that the inner surface of the clamping-disk B isprovided with guides b b in pairs, and it may be here stated that theseguides are exactly like those described in connection with the fixeddisk A both as. regards their number and position. Fig. 2 shows that thecentral opening of disk B ts upon the turned outer surface of theenlargement of hub ct of disk A and that the disk B is loose on the huba and not secured in any way thereto. The hub of disk A is adapted to besecured upon a driving ordriven shaft in any common Way. Between the twodisks are located the segments. (See Fig. 2.) That shown is marked byletter C. The u'ppermost surface (designated by letter c) is thebelt-face of the segment. The extent and customary contour of this faceand portion are 4shown in Fig. l. Vertically arranged upon oppositesides of the segment-body are the fins or feathers c c, which enter thespaces between the pairs of guides falling opposite each other on thetwo disks.' Midway of the lower part of the segment is the block c2,usually an integral part of the segment. This block is bored andinteriorly threaded to en- IOO gage a screw D, that has a shoulder d incontact with the outside of the enlargement of hub ct, and an unthreadedportion passing through the hub and secured to a miter gearwheel E,located within the before-mentioned cylindrical cavity 0,2 of fixed diskA. The ruiter-gear touches the inner surface of the cavity and, togetherwith the shoulder CZ, prevents the longitudinal displacement of screw D.Outside and inside the surface of the hub a may be slightly flattened toafford sufficient bearing for the shoulder' and gear. Gearwheel E mesheswith a second miter gearwheel F, the hub of which is marked f, and inthe hub a hole f is bored, as shown, parallel with its axis, and thishole will be again referred to. G, and a portion g of this sleeve iseXteriorly threaded. The unthreaded part of sleeve G extends far enoughout of h ubfof gear-wheel F to afford a bearing for the circularpressure-plate H, which is provided with a central opening fitting thesleeve, as drawn. Pressure-plate H has an inwardly-turned rim h and anannular raised portion t immediately around its central opening. Thisannular raised portion is furnished with a notch or groove h2, (see Fig.7,) adapted to engage the tooth of a spring-catch, to be laterdescribed. Projecting inwardly from plate H and having one end securelyfixed therein is the pin J, that registers with and movably its into thehole f in the hubfof miter-gear F, above mentioned. It is now believedto be clear that if the pressure-plate H is turned while the pin is inthe hole the gear F must turn with it. It follows also that miter-gear Eand screw D must be turned at the same time and the segment moved out orin, its path directed by the guides of the disks, as plainly indicated.Furthermore, it will be understood that the pressure-plate may be movedto the right or left upon the sleeve, thus withdrawing the pin orcausing it to further enter the hole. To move the pressureplate in or topermit it to be moved outwardly and to rotate it, and consequentlyrevolve the gearing, is the ofce of hand-wheel K. Handwheel K has a hubla, interior-ly threaded and in engagement with the threaded portion gof sleeve G. Obviously if the hand-wheel, not being connected in any waywith the plate H, were turned in such manner as to cause it to move tothe left along the sleeve it would force the pressure-plate to the left,which in its movement would press the movable or clamping disk in thesame direction, and thus the segment would be securely clamped betweenthe two disks 5 but unless the hand-wheel can be in some mannerconnected with the pressure-plate when need be neither the plate nor thegearing could be rotated and the segments could not be adjusted in orout. I therefore provide a lever L, pivotally supported by thehand-wheel in any effective way and having a tooth Z,adapted to enterthe notch 71,2 in the annular raised Gear F is keyed upon a sleeve'portion of the pressure-plate. The toothed extremity of the lever L ispressed upon by a coil-spring M, making it, in fact, a springcatch, asstated. With the tooth in the notch the hand-wheel, pressure-plate,sleeve G, and gearing all turn, and the segment is moved either in orout, decreasing or enlarging the belt-wheel body in the usual way. Whenthe pulley is in use, the segments are clamped between the disks A andB, and if a new adjustment is desired the hand-wheel is screwed to theright or outwardly upon sleeve G, the tooth Z of lever L being raisedout of the notch h2 prior to this movement. After the hand-wheel hasthus relieved the pressure upon plate H, and consequently from disk B,no difficulty is experienced in adjusting the segments. It will be notedthat when the tooth Z of the lever L is again caused to engage the notchh2 in the pressure-plate H and, as stated, the hand-wheel K, thepressureplate H, the sleeve G, and the gear-wheel F are all connectedtogether and turn as one piece upon the shaft the threaded hub 7c of thehand-wheel does not move either to the left or right upon the threadedportion g of the sleeve G, because the sleeve turns also. Pressure plateH is therefore not forced against the loose clamping-disk B and noclamping of the segments results. After the segments have been adjustedeither toward or from the center by means of the gearing and the screwsD, during which all the connected parts just mentioned turn together,then the tooth Z of the lever L is once more raised out of the notch71,2 and so held while the hand-wheel is turned. Now the pressureplate His no longer rotated by the handwheel and the gear F and sleeve G do notturn, although the hole f' in the gear-wheel still engages pin J,projecting from the pressure-plate H. The sleeve remains stationary, andthe hub 1c of the hand-wheel K acts as a nut on the sleeve and may bescrewed to the left against the pressure-plate H, which in turn pressesagainst the disk B, thus clamping the segments after adjustment betweenthe fixed disk A and clamping-disk B and holding them securely in place.Fig. 2 shows the segments so clamped. The office of the collar N, havingset-screw n, is to take up the reaction of sleeve G, the sleeve beingforced to the right as the hub 7c presses plate H tothe left. The collar'also limits the movement of the hand-wheel to the right.

I am aware that expansible pulleys have been constructed in which thesegments are moved to and from the center by means somewhat similar tothose herein shown and described, and I do not claim those features.

What I claim, and desire to secure by Letters Patent of the UnitedStates, is-

1. In an expansible pulley, the combination of a relatively-fixed disk,segments adj ustable toward or from the center of the pulley, means forguiding the segments, a loose clamping-disk, and mechanism constructedIOO IIO

and arranged to adjust the segments and to operate the said looseclamping-disk whereby the segments may be clamped between the two disksafter adjustment, substantially as described.

2. In an eXpansible pulley, the combination of a relatively-fixed disk,a loose clamping-disk, each of the said disks having radial guides uponits inner surface, segments adjustable within said guides toward or fromthe center of the pulley, a pressure-plate, and mechanism constructedand arranged to adjust the segments and to force the pressureplateagainst the loose clamping-disk whereby the segments may be clampedbetween the two disks after adjustment, substantially as described.

3. In an expansible pulley, the combination of a relatively-fixed diskhaving a hub possessing an internal cavity, a loose clamping-disk havinga central opening encircling the said hub of the fixed disk, each ofthedisks having radial guides upon its inner surface, segments adjustablein the said guides segments and having unthreaded portions r passingthrough the said hub into the cavity therein, gear-wheels located insaid cavity and adapted to turn the said screws, a sleeve attached toone of the gear-wheels and having a threaded portion, a pressure-platemovable laterally upon the said sleeve and arranged to be forcedVagainst the loose clamping-disk, eXtensible connections between thepressureplate and gearing, a threaded hand-wheel engaging the threadedportion of the said sleeve, devices whereby the hand-wheel and pressure*plate mayi be detachably connected, and a collar N having a set-screw,substantially as described.

In testimony whereof I affix my signature ,in presence of two witnesses.

Witnesses:

NEWTON P. FRYE, CLiARLEs H. LITTLEFIELD.

